LEOPOLD, Ind. — On the ceiling of Abbie Brockman’s middle school English classroom in Perry County, the fluorescent lights are covered with images of a bright blue sky, a few clouds floating by.Outside, the real sky isn’t always blue. Sometimes it’s hazy, with pollution drifting from coal-fired power plants in this part of southwest Indiana. Knowing exactly how much, and what it may be doing to the people who live there, is why Brockman got involved with a local environmental organization that’s installing air and water quality monitors in her community.“Industry and government is very, very, very powerful. It’s more...